minister calls it a declaration of war. secretary of statejohnkerryissuesa new warning to russia next on pbs "newshour weekend." >> pbs "newshour weekend" is made possible by louis b. and louise coleman. judy and josh westin. the walloch family, rosalynn p. walter. corporate finding provided by mutual of america designing customized individual retirement. that's why we're your retirement company. additional support is provided by -- and by public broadcasting and contributions from pbs viewers like you. thank you. from the tisch studios linc center in new york hari sreenivasan. >> thank you for joining us. international crisis surrounding ukraine benefitsified with many experts describing the situation as the greatest threat to east-west relations since the cold war. russian troops invade territory of crimea in the last hours today surrounded ukrainian mirlts. the prime minister of ukraine said that action brought the neighboring companies within what he described as a few inches of war. >> this is the red alert. this is not the threat, this is the actually the declaration of war to m